Machine for joining veneer sheets



Feb. 8, 1955 o. B. NYSTROM MACHINE FOR JOINING VENEER SHEETS Filed 001:.51 1951 (0 6 7 47 gm, WWQ

United States Patent MACHINE FOR JOINING VENEER SHEETS Olof BirgerNystrom, Sundsbruk, near Sundsvall, Sweden, assignor, by mesneassignments, to Adolf Friz G. m. b. H., Stuttgart-Bad Cannstatt, Germanybetween a lower pressing device provided with conveyance apparatus andan upper pressing device provided with contact-pressure roll, and theveneer edges to be joined are pressed together.

The tensionally connected joining of the upper with the lower pressingdevice was performed in the prior machines by means of an arm startingfrom the side of the machine frame and extending laterally in a curveover at least a part of the veneers to the upper pressing device andwhich, especially when veneer strips of great width or in great numberwere to be joined, resulted not only in a considerable increase in praceof the machine and increase of its weight and material requirement, butwas also an obstacle in working and when shipping the machine.

This lateral arm, with all its disadvantages, can be eliminated entirelyaccording to the invention in that, for the connection of the upperpressing device with the lower pressing device, a beam is employed whichextends in the direction of strip feed and is supported on the frame ata point where the veneer edges to be joined do not yet touch each other.

These and other characteristics of the invention will appear from thefollowing detailed description, in which reference is had to theaccompanying figures of the drawing, said figures illustratingdiagrammatically an example of one way of embodying a device accordingto the invention.

Figure 1 shows a side view of a machine arranged in accordance with theinvention and intended for the edgewise joining of veneer panels and thelike by gluing.

Figures 2, 3 and 4 show cross sections of the machine on the lines 2--2,3-3 and 44, respectively, of Figure 1.

In the drawing, 2 designates a lower stationary press member, on whichan upper movable press member 3 is adapted to rest freely, orsubstantially freely, with its entire weight. manner, provided with anumber of rolls 4, the axes 5 of which (Figure 4) preferably form anangle both with each other and with the direction of feed of the objectsto be joined, so that the veneer sheets, on which glue has been applied,will under the influence of the pressure of the press member 3 bepressed against each other in a sideways direction when being movedforward between the press members, for example, by means of conveyingmembers provided on the lower press member. Said conveying members mayconsist of endless conveying belts or the like 6. For the purpose ofdrying and hardening the glue in the joint the press members areprovided with heating bodies 7, 8 of a known kind. In front of the pressmembers 2, 3 there is a section, comprising means for conveying theveneer sheets to be joined up to and for introducing them between thepress members. Furthermore, there are means for guiding, during the saidfeeding operation, the panels in the desired manner, indicated in theopening paragraph of the specification, and for providing them with glueon the edges or surfaces along which the joining is to take place. Suchmeans will be described more particularly in the following.

The veneer panels to be joined are delivered to the press members over afeed table having a wide horizontal bed 9 adjacent the entrance end ofthe press, and

The press member 3 is, in a known 4 separate feed table sections 10, 11for the individual panels; the table sections 10 and 11 being indifferent planes which merge into the common horizontal feed bed 9. Forexample, the table section 10 may be in the horizontal plane of the bed9 throughout its length, whereas the table section 11 may slopedownwardly towards the bed 9. The stationary press member 2 iscountersunk or grooved to receive the conveyor belts 6; the arrangementpreferably being such that the upper surface of the conveyor belts is inhorizontal alinement with the surface of the feed table 9 and slightlyabove the surface of the press member 2. An elongated beam comprising anupper horizontal Web 12 and a vertical supporting web 13, is integralwith or secured to the feed table between the sections 10 and 11, andextends in the direction of the feed of the veneer panels. Guidesurfaces are provided for the opposed edges of the veneer panels as theyare advanced towards the feed table 9, and preferably, as shown in Fig.2, by grooves 14, 15 which extend along opposite sides of the verticalWeb 13 of the longitudinally extending beam. The lower surfaces of theguide grooves 14 and 15 are extensions of the planes of the feed tablesections 10 and 11, respectively, and the root surfaces of the groovesare alined in a vertical plane. The beam 12, 13 does not extend alongthe entire length of the feed table sections 10, 11 and additional guidemeans such as a fillet or rib 16, Fig. 3, may be provided on the feedtable in advance of and/or beyond the beam.

The veneer panels or strips are pressed against the table sections 10and 11 by idler feed rolls carried by arms 17 pivoted on the web 13 andbiased by their weight and/or by springs 18 to press the supportingmeans 19 of idler rolls 20 towards cooperating driven feed rolls 21.

The upper web 12 of the beam constitutes a support and lateralstabilizer for the elongated bar member 22 which positions the upperpress member 3. The bar member is of rectangular strap form at the web12 and is clamped in a groove to the upper surface of the Web 12 by ahinged plate 23. The forward end of the bar 22 is pivotally connected bya pin 24 to the forward end of the casing 25 of the press member 3 andhas a snug sliding fit between parallel flanges 26 which extend upwardlyfrom the casing 25 at the rear end. For rigidity, the bar 22 ispreferably of inverted channel cross-section in advance of the strapportion which is clamped to the web 12. The forward end of the pressmember 3 bears, by gravity and/or the resiliency of the bar 22 upon theveneer panels in transit through the press, and a uniform or a graduateddistribution may be obtained by adjustable pressure means located at oneor more points between the supporting bar 22 and the casing 25 of thepress member 3. The pressure means may be, as shown in Fig. l, a flange27 on casing 25, and a screw 28 threaded through the bar 22 to bear upona spring 29 seated on the flange 27.

The glue applying device, which is of a kind known per secomprising avertical glue collecting roll 31, dipping into a receptacle 30 for theglue, and a slanting glue applying roll 32 in contact with the formerroll-is provided adjacent the feed-in rolls 20, 21 where the adjacentedges of the panels to be joined are in vertical alinement with butvertically spaced from each other. Hereby the veneer edge to be coatedwith glue will be held in a suitable position for the glue to beapplied.

It has proved that by means of a device according to the invention verygood results will be obtained, particularly when joining veneer panelsby means of gluing, because the panels need not be subjected to lateralbending stresses when applying the glue and at the same time a device isobtained that will effectively guide the panels and keep them pressedtogether during the passage through the drying zone. Furthermore, it isattained that the upper movable press member can be held in position onthe lower stationary press member without necessitating the provision ofa yoke or an arm extending from the frame of the machine. said yoke orarm limiting the width of operation. Moreover, the press members may bequickly and easily removed for cleaning and so on.

Having now described my invention, what I claim as new and desire tosecure by Letters Patent is:

1. In a veneer joining machine, a lower press member, a frame includingtables for supporting veneer strips to be joined, conveyor means foradvancing the veneer strips over said tables and said lower pressmember, means guiding the veneer strips from initial positions on saidtables with their opposed edges in different planes to final positionson said lower press member with their opposed edges in contact, an upperpress member for pressing the veneer strips to said lower press member,and means mounted on said frame between said tables for supporting saidupper press member; said supporting means extending in the direction ofmovement of said veneer strips.

2. In a veneer joining machine, the invention as recited in claim 1,wherein said supporting means includes a beam secured to said frame, abar carried by said beam, and means connecting said upper press memberto said bar for angular movement of said upper press member about ahorizontal axis.

3. In a veneer joining machine, the invention as recited in claim 2,wherein said connecting means includes means preventing lateral movementof said upper press member with respect to said supporting means.

4. In a veneer joining machine, the invention as recited in claim 1,wherein said supporting means includes a beam secured to said frame, andsaid guiding means comprises grooves in said beam, the opposed edges ofthe veneer strips being seated against and guided by the roots of therespective grooves as they are moved over said tables.

5. In a veneer joining machine, the invention as recited in claim 4,wherein the roots of the respective grooves are located in the samevertical plane, whereby the veneer strips are moved Without lateralshifting from their initial positions on said tables to their finalpositions on said lower press member.

References Cited in the file of this patent UNITED STATES PATENTS1,010,846 Black Dec. 5, 1911 1,771,105 Williams July 22, 1930 2,196,326Robinson Apr. 9, 1940 2,269,816 Gustin Jan. 13, 1942 2,351,946 FriZ June20, 1944 2,516,280 Welch July 25, 1950 2,544,133 Carlson Mar. 6, 19512,571,604 Payzant Oct. 16, 1951

